Apparatus for forming metallic articles



Feb. 13, I E 5|RP ETAL API'ARATUS FOR FORMING METALLIC ARTICLES Filed March 27, 1943 2 Sheets-Sheet 1 IN VEN TORS E. S/EP J. 52 Sruu.

HTTOENE K Feb. 13,1945. E. SIRP ETAL 2,369,318

APPARATUS FOR FORMING METALLIC ARTICLES Filed March 27, 1943 2 Sheets-Sheet PA HIM I INVENTORS E 512/ J. 8. 5701.1.

ATTORNEY A Patented Feb 13, 1945 APPARATUS FOR FORMING METALLIC ARTICLES Emil sir Downers. Grove, and John. 5. Stull, Chicago, Ill., assignorslto Western, Electric Company, Incorporated; NewtYork, N. Y., a corporation of New York 1 AppIicationMarchZ'Z'Q1943,.Serial No. 480,826 r (o1. se m) h p 5' Claims. This invention relates to: an forming metallic articles;

In the manufacture of some typesofivacuum. tubes, the glass envelope of the tube is fixed inn apparatus for a funnel-shaped metallic. part. Due to the difference in the coefiicients of expansion of the metal part and the glass envelope,it is desirable to form the funnel-shaped portion of the metallic member with a thin enough cross section to permit it to expand and contractto the same extent as the glass Heretofore, the forming of such parts has been exceedingly difiicult due to the fact that the. cross section of thepart being of r it. i A

It is an object of the present invention to provide an apparatus for forming irregularly shaped metallic parts. of thin cross section; a i In accordance with one embodimentof the invention, a substantially funnel-shapedpart, hay"- and forrned is so thin that the cutting tools bend. the

part rather than cutting a part of the metal off ing the hollow conical portion thereof provided" withlrelatively thick walls, is rotated about the ax s of the part and cutting tools diametrically opposed one to another are advanced into-engagement with opposite sidesuof the wall of the hollow conical portion of the blank whereby, when the blank is rotated, the cutting knives will serve the double purposeof cutting a part of the metal away to form the desiredithin-walled section, gradually tapering to a thicker wall as the apex of the conical portion is approached, and

of acting as supports for thewall being-formed. The cutting tools are advancedtoward the blank and are guided, cams 50 that, 1 the cutting 35 in any suitablemanner while holding the blank against longitudinal movement;- The chuck and.

proceeds, the tools. move apart slightly While retainin their cutting. surfaces diametrically opposed with respect one to another.

A better understanding of the invention may of the tool holders and camswhich guide the tool holders; i i

i Fig. 4 is a greatly enlarged fragmentary sectional view showing the position of the cutting tools at the beginning of the operation in dot and. dash'lines and the position of the cutting tools at the end of the operation insolid lines;

Fig; 5 is a fragmentary sectional view on substantially the same scale as Fig. 4 showing a glassenvelope mountedinthe article formed by the presentapparatus.

Referring to the drawings, wherein like reference characters designate the same parts throughout theseveral views, it will be seen that the partto be formed; as shown in Fig. 5, comprises a main body portion Ill having a hollow frusto-conical portion ll, into whichaglass en-. velope l2 of a vacuum tube is to be set. .It-

should be noted that the walls of the portion H of the article increase in thickness gradually from an exceedingly thin cross section at the right end thereof (Fig. 5) to the point designated 13 and that the gradual increase inthickness becomes a more rapid increase from the point designated l3 to the endof the, cut, as shown at l4. The

blank from which this article is to be formed is shown in, Fig. 1 and may be formed to the shape as shown therein in any suitablemanner preparatory to being operated upon by the apparatus shown herein. A blank which has been Jormed to theconfiguration shown in-F'ig. 1 may be placed in any suitablechuck l8, which may be rotated to rotate the blankabout its own axis other portions of the apparatus are mounted upon abed 19,, which serves to support the apparatus and may comprise the bed of any screw bE had by efe enc tothe followingv detailed mimachine or other mechanism for imparting roscription. when considered in conjunction with the accompanying drawings, wherein a Fig. 1 is aplan viewof apparatus embodying the invention showing the cutting tools in thei retracted, inoperative position;

in the direction ofthe arrows showing the end hold- 50 tation to the chuck l8. Mounted upon the bed Hare a pair of cams 2 0 and 2|, which may be adjustably' mounted on the bed l9 by means of machine screws 22- and 23, respective1y. cams. 20 and 2| serve toguide the cutting tools, aswill be described more in detail hereinafter.

Reciprocablymounted with respect to the bed I9 is a cutter carryinghousing 25having a pair of posts 26 and 21 extending upwardly from the base thereof for entering apertures 28 and 29 i in tool supports 30 and 3|, respectively. The ap-. erture 2,8. is cylindrical and the-tool support 311 is thus pivotally mounted on the: post 26., whereas the aperture 29 is elongated slightly to performation of the tools and the. relative position u mit longitudinal movement of the tool support 3| as well as relative movement thereof about the post 21. Fixed in the tool supports 30 and 3| are a pair of cutting tools 32 and 33, which may be held in place by means of machine screws 3434. -It should be noted that the tools are directly opposite one to the other and thus will serve to prevent each other from bending the wall being formed. The two toolsupports 30 and 3| are urged to move away from each other by a compression spring 35 mounted in a pocket 36 formed in the tool support 3| and bearing.

against the tool support 30. 'The tool supports are thus urged apart and into engagement with abutment screws 31 and 38 threaded into the side walls of the housing 25 and lockedin adjusted position therein by lock nuts 39 and 43. The tool supports 30 and 3| have cam rollers 43 and 4| mounted beneath them for engagement with cams 20 and 2| as the housing 25 isrnoved. to the left (Figs. 1 and 2). In addition to car rying the rol1er 4| extending from its undersurface, the tool support 3| has an adjustable abut.- mentscrew 42 threaded into a post 43 depending from itsun'dersurface. a The post- 43' extends through an aperture 44 formed in thebottom of the housing 25 and the .post 43 mayhave the adjustable abutment screw 42 locked in position with respect to it by means of a lock nut 45."

Seated in the right hand wall (Figs. 1 and 2) of the housing 25 is acompression spring 43, which is set into a socket 41 and urges a cylindrical plunger 48 against the right edge (Fig. 2) of the tool support 3|, thereby to hold the right hand surface of the aperture 29 against the post 21', thus tending tohold the tool 33 advancedsomewhat to the left. The bed. l9 of the appa ratus has an abutment'member 50 positioned "on it which extends upwardly into the path of the abutmentscrew 42 and 'aft'er the tools have-been advanced to the. position as shown in Fig. 2, the

abutment screw 42 will strike the abutment'member 50 and the toolsupport'3l will be held sta-H travelling up'this slopeto cut the blank up tothe point I 3, the slope of the cam becomes more gradual to thereby advance the tool 3| less rapidly and gradually lessen the'depth of cut formed by the a tool 3| and increase 'thethicknes s of the wall of the portion H of the blank. b H

A better understanding of the apparatus may be had by reference to'the following brief description of the operation thereof. After a blank hasbeen formed to the shap'e'shown in Fig. 1

by any suitable machining or milling operations, the blank may be placed in'the chuck l8 and rotated about its ownaxis. While the blank is beingrotat'ed, the housing 25 maybe advanced-iii any suitable manner, for example," by operation;

of "the'manually 'actuatablelmechanisms (not shown) to advance the'tools 311 and 32 straight .towards the right hand edge of the blank, as

viewed in Fig. 1 As the t'o-ols advance toward the blank, the cam rollers 4|] and- 4! wilfstrike the surface of theicam's 20 and 21, which will move the tool holders 30f and 3| toward each other'until bo'thbof the tools engage the right band edge of the frusto-coriical shaped portion of the blank and begin the cutting operation. As soon as the cutting operation begins, the cam roller 40 will engage the receding portion of the cam and while the tool carrier-3| continues to rock clockwise, being driven by its cam roller 4|, the tool carrier 30 will also rock-clockwise,

thus to cutthe portion of the blank between its right hand end and the point l3. As soon as the tools which are held diametrically opposite one to another reach the point |3 on the blank, the cam roller 4| will reach the gradually sloping portion of the cam 2| and while the tool holder 30 and tool 32 continue to move in a straight line a the cam roller rolls down the surface of the cam 20, the spring 35 will urge the tools to move apart and the tapering portion between the points- I3 and I4 on the blank, as shown in Fig. 5, will be formed. Y As soon as the tools reach the position shown in Fig. 2, continued movement to the left, of the tool carrier 3|, will be stopped by the engagement of the abutment screw 42 with the abutment 5|] and while the tool 32 continues to perform its cutting operation to complete the formation of the blank, the tool 3| will be held stationary. After the blank has thus been completely formed, the housing 25 may be moved back to the position shown in Fig. l and the operation ma be repeated one. new blank. What is claimed is: 1. An apparatus for forming a substantially funnel-shaped part with the hollow frusto-conical portions walls tapering comprising means for rotating the blank about its own axis, inner and outer cutting tools, means for resiliently urging said tools apart, means for supporting the tools for movement at angles to the axi ofrotation of a part and for holding said tools in a position where they will act as supports for the wall being formed between them, and cam means for overcoming said resilient means to move the tools at different angles to the axis of rotation of the blank.

2. An apparatus for forming a substantially funnel-shaped part with the hollow frusto-coni- I cal portions walls'tapering comprising means for rotating the blank about its own axis, inner and outer cutting tools, means for resiliently urging said tools apart, means for supporting said tools eccentrically of the axis of rotation of the blank.

'blank, cams for guiding said tools for movement cams for guiding said tools for movementat different angles to the axis of rotation of the blank,

and means for reciprocating the tools with respect to the blank.

3. An apparatus for'forming a substantially funnel-shaped part with the hollow frusto-conical portions walls tapering comprising means for rotating the blank about its own axis, inner and outer cutting tools, means for resiliently urging said tools apart, means for supporting said tools eccentrically of the'axis of rotation of the at different angles to the axis of rotation of the blank, means for reciprocating the tools with respect to the blank, and means for stopping the reciprocation of one tool prior to the stopping of the reciprocation of the other tool.

4. An apparatus for forming a substantially funnel-shaped part with the hollow frusto conical portions walls tapering comprising means for rotating th blank about its own axis, inner and outer cutting tools, means for resiliently urging said tools apart, means forysupporting said tools eccentrically of the axis of rotation of the blank,

camsfor guiding said tools" for movement at different angles to the. axis of rotation of the blank,

means for reciprocating the tools with respect to the blank, and means for stopping the reciprocation of one tool prior tothe stopping of the reciprocation of the other tool including a movable abutment member movable with the tool, a

fixed abutment member for cooperation with the movable abutment member and means for resiliently urging said tool to continue movementwith the other tool. v

5. An apparatus for forming a substantially funnel-shaped part with the hollow frusto-conical blank, and means for reciprocating the tools with i respect to the blank.

EMIL SIRP. JOHN s. STULL. 

